There are many failure conditions in multiphase and parallel converter type voltage regulators where the voltage regulator may still provide regulation under some conditions, but will fail when the operating conditions change. In some cases, the failures may be catastrophic, if the failure condition is undetected and the voltage regulator is operated significantly beyond its operating limit, and may result in a significant exothermic event where component and system damage may be alarming, and possibly even cascade into a more serious event. In addition to output voltage sense circuits, voltage regulators make use of current sense circuits which enable the controller to monitor the current flowing through critical components in a regulator, such as power switches or the output inductor, for regulation, control, telemetry, and protection. In the case of an open current sense line, through faulty manufacturing or component failure, the open current sense line failure may be undetected by the controller, which will continue operating the voltage regulator as if no failure exists, but with faulty current sense information. By operating with faulty current sense information, the voltage regulator may operate significantly beyond the operating limits of the power components.
Thus, there is a need for a mechanism to detect open current sense lines in multiphase and parallel converter type voltage regulators.